Can I ask a stupid question? I've only come across anchors like this once, and while the final anchor was solid, the process was nothing short of comical. Complete with rapping off trees and ropes and anchors everywhere. And then there was cleaning the thing... I must of walked up and down more times than I climbed it.

So what's the 'standard' procedure for a toprope anchor that is over an edge? Is there one?

Edit: Oh and there were no rap rings, so no, I wasn't going to rap off just the hangers...

Yes, there is a standard procedure. In a nutshell...

Bring a length of static rope and a Gri-gri with you to the crag. Fix the rope to a BFT, and then rap over the edge with the Gri-gri. Set up your anchor and then use the Gri-gri to ascend the rope back to the top. Make sure you have a knot in the rope below you to back up the Gri-gri.